In biology, determination is the process of matching a specimen or sample of an organism to a known

taxon In biology, a taxon (back-formation from ''taxonomy''; : taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular name and ...

, for example identifying a plant as belonging to a particular

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

. Expert taxonomists may perform this task, but structures created by taxonomists are sometimes used by non-specialists. Modern tools include single or multi-access

identification key In biology, an identification key, taxonomic key, or frequently just key, is a printed or computer-aided device that aids in the identification of biological organisms. Historically, the most common type of identification key is the dichotomous k ...

s, which can be printed or computer-assisted.

Overview

The need to identify which plant is which has existed for time immemorial. The ability depends to a large extent on what criteria and whose system is used. Determination now relies on modern

taxonomy image:Hierarchical clustering diagram.png, 280px, Generalized scheme of taxonomy Taxonomy is a practice and science concerned with classification or categorization. Typically, there are two parts to it: the development of an underlying scheme o ...

to identify organisms. Taxonomy is the branch of biology which deals with identity, nomenclature and classification. The term was first coined in 1813 by Swiss botanist

Augustin Pyramus de Candolle Augustin Pyramus (or Pyrame) de Candolle (, , ; 4 February 17789 September 1841) was a Swiss people, Swiss botany, botanist. René Louiche Desfontaines launched de Candolle's botanical career by recommending him at a herbarium. Within a couple ...

Carl Linnaeus Carl Linnaeus (23 May 1707 – 10 January 1778), also known after ennoblement in 1761 as Carl von Linné,#Blunt, Blunt (2004), p. 171. was a Swedish biologist and physician who formalised binomial nomenclature, the modern system of naming o ...

, who began modern taxonomy, used the term 'systematics' himself. Determination then requires comparisons of certain characteristics and then assigning a particular specimen to a known taxonomic group, hopefully ultimately arriving at a species or

infraspecific name In botany, an infraspecific name is the scientific name for any taxon below the rank of species, i.e. an infraspecific taxon or infraspecies. The scientific names of botanical taxa are regulated by the ''International Code of Nomenclature for al ...

. The characteristics used are usually morphological, such as colours, numbers, shapes and sizes of particular organs. Where possible, this is traditionally done using dichotomous keys. Keys are traditionally found in such works such as floras,

field guide A field guide is a book designed to help the reader identify wildlife (flora or fauna or funga) or other objects of natural occurrence (e.g. rocks and minerals). It is generally designed to be brought into the " field" or local area where suc ...

s or

monograph A monograph is generally a long-form work on one (usually scholarly) subject, or one aspect of a subject, typically created by a single author or artist (or, sometimes, by two or more authors). Traditionally it is in written form and published a ...

s. Botanical or entomological keys have been coded as computer programs. Applications are even available now which use artificial intelligence to identify plants on the basis of photographs. There are not always keys available for certain regions or plant groups, and the person determining the specimen will then have to rely on characteristics in the

species description A species description is a formal scientific description of a newly encountered species, typically articulated through a scientific publication. Its purpose is to provide a clear description of a new species of organism and explain how it diff ...

or discovered through comparison of multiple specimens with the

type Type may refer to: Science and technology Computing * Typing, producing text via a keyboard, typewriter, etc. * Data type, collection of values used for computations. * File type * TYPE (DOS command), a command to display contents of a file. * ...

. Using

DNA barcoding DNA barcoding is a method of species identification using a short section of DNA from a specific gene or genes. The premise of DNA barcoding is that by comparison with a reference library of such DNA sections (also called " sequences"), an indiv ...

is a modern method that does not require the determiner to be highly trained. Another similar method uses the

alkaloid Alkaloids are a broad class of natural product, naturally occurring organic compounds that contain at least one nitrogen atom. Some synthetic compounds of similar structure may also be termed alkaloids. Alkaloids are produced by a large varie ...

profiles of specimens to determine the species. The total weight or length of the

genome A genome is all the genetic information of an organism. It consists of nucleotide sequences of DNA (or RNA in RNA viruses). The nuclear genome includes protein-coding genes and non-coding genes, other functional regions of the genome such as ...

as measured in

base-pair A base pair (bp) is a fundamental unit of double-stranded nucleic acids consisting of two nucleobases bound to each other by hydrogen bonds. They form the building blocks of the DNA double helix and contribute to the folded structure of both DNA ...

s can be used to identify species.

Paleontologist Paleontology, also spelled as palaeontology or palæontology, is the scientific study of the life of the past, mainly but not exclusively through the study of fossils. Paleontologists use fossils as a means to classify organisms, measure geolo ...

s must be able to identify their specimens based only on the shapes and sizes of fossilised bones. In forestry, especially in the tropics, identifying trees based on the flowers or leaves high up in the crown can be difficult, a method of identifying tree species in this case is called a 'slash', a shallow machete cut to the trunk to expose the colours of the different layers inside, and show the type of sap. The science of identifying plant species using their

pollen Pollen is a powdery substance produced by most types of flowers of seed plants for the purpose of sexual reproduction. It consists of pollen grains (highly reduced Gametophyte#Heterospory, microgametophytes), which produce male gametes (sperm ...

is called

palynology Palynology is the study of microorganisms and microscopic fragments of mega-organisms that are composed of acid-resistant organic material and occur in sediments, sedimentary rocks, and even some metasedimentary rocks. Palynomorphs are the mic ...

. Geography can also sometimes help in narrowing down the identity of a specimen. Sometimes the determiner will be unable to identify a specimen clearly, and use such additions as ''

cf. The abbreviation cf. (short for either Latin or , both meaning 'compare') is generally used in writing to refer the reader to other material to make a comparison with the topic being discussed. However some sources offer differing or even contr ...

'' or '' aff.'' to convey this. Reference collections of identified plant specimens are collected into

herbaria A herbarium (plural: herbaria) is a collection of preserved plant specimens and associated data used for scientific study. The specimens may be whole plants or plant parts; these will usually be in dried form mounted on a sheet of paper (called ...

. Most plant parts are dried, pressed, mounted on herbarium sheets and stored; succulents and some other types of plants are normally kept in alcohol solution. The sheets are standard size of 16 × 11 inches or 41.25 × 28.75 cm. The identified plant ideally includes all parts including roots, flowers and fruits, strobili, etc. Especially the flowers are important when trying to identify a specimen.

Computer-assisted identification

Automated species identification uses

artificial intelligence Artificial intelligence (AI) is the capability of computer, computational systems to perform tasks typically associated with human intelligence, such as learning, reasoning, problem-solving, perception, and decision-making. It is a field of re ...

to identify species based on the images of the species. Projects like

iNaturalist iNaturalist is an American 501(c)(3) nonprofit social network of naturalists, citizen scientists, and biologists built on the concept of mapping and sharing observations of biodiversity across the globe. iNaturalist may be accessed via its web ...

and Pl@ntNet relies on crowdsourced data and assists identification through automatic as well as community input.

References

External links

Shoot (over 19,000 plants listed)Visual Interactive Kingdom Plantae to division (Louisiana State University)Interactive Plant Identifier (University of Wisconsin)Interactive Plant Identifier (Auburn University)
{{Webarchive, url=https://web.archive.org/web/20151209202435/http://www.ag.auburn.edu/hort/landscape/leafid/index.php , date=2015-12-09
Image-based plant identification system (French Flora, Pl@ntNet project)Plants for identification on iNaturalistAnimals for identification on iNaturalistFungi for identification on iNaturalistMushroom identification demo on KindwiseInsect identification demo on KindwisePlant species identification demo
Botany

Overview

Computer-assisted identification

See also

References

Further reading

External links